This contribution reports ethylene polymerization behavior of titanium complexes incorporating bis(phenoxyimine) ligands. Six phenoxy-imine Ti(IV) complexes {6-R

1

-2-[CH=N(2

6-difluoro-3

5-diR

2

-4-R

3

Ph)]C

6

H

3

O}

2

TiCl

2

(

1

: R

1

= H

R

2

= H

R

3

= H;

2

: R

1

= H

R

2

= H

R

3

= 4-vinylphenyl;

3

: R

1

= CH

3

R

2

= H

R

3

= H;

4

: R

1

= CH

3

R

2

= H

R

3

= 4-vinylphenyl;

5

: R

1

= CH

3

R

2

= F

R

3

= H; 6: R1 = CH

3

R

2

= F

R

3

= 4-vinylphenyl) have been synthesized and evaluated for ethylene polymerization using dried MAO (simplified as DMAO) as cocatalyst. An obvious catalytic heterogeneity of Cat

2

(Complex

2

/DMAO) towards ethylene polymerization was observed

which was illustrated by decreased activity

multimodal molecular weight distribution and partially improved particle morphology comparing with Cat

1

. Moreover

Cat

3

exhibits "living" characteristics in the process under certain conditions (25 ℃

less than 20 min). Otherwise

the moderate to high ethylene polymerization activity of

ca

. 10

5

−10

6

g PE/(mol Ti·h) and high molecular weight (

M

w

= 10

5

−10

6

) of polyethylene can be obtained by changing the skeleton structure of these complexes.